387.字符串中的第一个唯一字符.py

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# @lc app=leetcode.cn id=387 lang=python3
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# [387] 字符串中的第一个唯一字符
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# https://leetcode.cn/problems/first-unique-character-in-a-string/description/
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# algorithms
# Easy (54.84%)
# Likes:    552
# Dislikes: 0
# Total Accepted:    299.2K
# Total Submissions: 545.1K
# Testcase Example:  '"leetcode"'
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# 给定一个字符串 s ，找到 它的第一个不重复的字符，并返回它的索引 。如果不存在，则返回 -1 。
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# 示例 1：
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# 输入: s = "leetcode"
# 输出: 0
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# 示例 2:
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# 输入: s = "loveleetcode"
# 输出: 2
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# 示例 3:
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# 输入: s = "aabb"
# 输出: -1
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# 提示:
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# 1 <= s.length <= 10^5
# s 只包含小写字母
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# @lc code=start
class Solution:
    def firstUniqChar(self, s: str) -> int:
        map = {}
        for i in s:
            if i in map:
                map[i] +=1
            else:
                map[i] = 1
        for i in map.keys():
            if map[i] ==1:
                return s.index(i)
        return -1
# @lc code=end